In what officials called the "best lead'' of the nearly 2-week-old aviation mystery, a satellite detected two large objects floating about 1,600 kilometers (1,000 miles) off the southwestern coast of Australia and halfway to the desolate islands of the Antarctic. The area is so remote is takes aircraft longer to fly there _ four hours _ than it does for the search.
The development raised new hope of finding the vanished jet and sent another emotional jolt to the families of the 239 people aboard.
Australian authorities said in a statement early Friday that the search had turned up nothing so far. Efforts were resuming with the first of five aircraft _ a Royal Australian Air Force P3 Orion _ leaving the base in Western Australia for the search around dawn. A civilian Gulfstream jet and a second Orion were expected to depart later Friday morning and a third Orion was due to fly out in the early afternoon to scour more than 13,000 square miles (35,000 square kilometers) of ocean.
A U.S. Navy P-8 Poseidon aircraft was scheduled to leave the base at about 4 p.m. (0600 GMT), but like the other planes, it will have enough fuel for only a few hours before returning to Perth.
"It is a very long journey to the site and unfortunately, aircraft can only have one or two hours over the search area before they need to return to the mainland for fuel,'' Warren Truss, who is currently Australia's acting prime minister while Tony Abbott is overseas, told Australian Broadcasting Corp. He said that weather conditions in the area were poor and may get worse.
"And so clearly this is a very, very difficult and challenging search. Weather conditions are not particularly good and risk that they may deteriorate,'' Truss said.
One of the objects on the satellite image was 24 meters (almost 80 feet) long and the other was 5 meters (15 feet). There could be other objects in the area, a four-hour flight from Australia, said John Young, manager of the Australian Maritime Safety Authority's emergency response division.
"This is a lead, it's probably the best lead we have right now,'' Young said. He cautioned that the objects could be seaborne debris along a shipping route where containers can fall off cargo vessels, although the larger object is longer than a container.
Truss said officials were working to get more satellite images and stronger resolution to help searchers get a better sense of where the objects are and how far they've shifted since the initial images were captured. "They will have moved because of tides and wind and the like, so the search area is quite broad,'' Truss said, adding that marker buoys were dropped to help get a better understanding of what drift is likely to have occurred.
The Norwegian cargo vessel Hoegh St. Petersburg, with a Filipino crew of 20, arrived in the area and used searchlights after dark to look for debris. It will continue the search Friday, said Ingar Skiaker of Hoegh Autoliners, speaking to reporters in Oslo.
The Norwegian ship, which transports cars, was on its way from South Africa to Australia, he said. The Australian Maritime Safety Authority said another commercial ship and an Australian navy vessel were also en route to the search area.
Satellite imagery experts said the lead is worth investigating.
"It would be very nice if you could see a whole wing floating there, then you could say, 'OK that's an airplane,''' said Sean O'Connor, an imagery analyst with IHS Jane's. In the case of these satellite images, "you can't tell what it is'' so closer examination is critical.
Another analyst said the debris is most likely not pieces of Malaysia Airlines Flight 370. There have been several false leads since the Boeing 777 disappeared March 8 above the Gulf of Thailand en route from Kuala Lumpur to Beijing.
"The chances of it being debris from the airplane are probably small, and the chances of it being debris from other shipping are probably large,'' said Jason Middleton, an aviation professor at the University of New South Wales in Sydney.
The development marked a new phase for the anguished relatives of the passengers, who have been critical of Malaysian officials for what the relatives say has been the slow release of timely information. While they still hope their loved ones will somehow be found, they acknowledged that news of the satellite images could mean the plane fell into the sea.
"If it turns out that it is truly MH370, then we will accept that fate,'' said Selamat Bin Omar, the father of a Malaysian passenger. The jet carried mostly Chinese and Malaysian nationals.
But he cautioned that relatives still "do not yet know for sure whether this is indeed MH370 or something else. Therefore, we are still waiting for further notice from the Australian government.''
Malaysian officials met with the relatives Thursday night in a hotel near Kuala Lumpur, but journalists were kept away. After the meeting, groups of people left looking distraught.
Hamid Amran, who had a child on Flight 370, said questions asked at the meeting made it "apparent that Malaysia's military is incapable of protecting its own airspace.''
He believes "that my child and all the other passengers are still alive. I will not give up hope.''
Malaysian Airlines CEO Ahmad Jauhari Yahya said the relatives in Kuala Lumpur were being given updates by high-level officials "two or three times a day.''
"We do take care of the next of kin,'' he said, adding that if the debris is located "close to Australia, we will obviously make arrangements to fly the next of kin there.''
A group of Malaysian government and airline officials flew Thursday night to Beijing to meet families there.
Young said the ocean in the search area is thousands of meters (feet) deep.
DigitalGlobe, a Longmont, Colo.-based company, said it provided the images to Australian officials. The Australian Maritime Safety Authority released two images of the whitish objects. They were taken March 16, but Australian Air Commodore John McGarry said it took time to analyze them.
"The task of analyzing imagery is quite difficult, it requires drawing down frames and going through frame by frame,'' he said.
The hunt has encountered other false leads. Oil slicks that were seen did not contain jet fuel. A yellow object thought to be from the plane turned out to be sea trash. Chinese satellite images showed possible debris, but nothing was found.
But this is the first time that possible objects have been spotted since the search area was massively expanded into two corridors, one stretching from northern Thailand into Central Asia and the other from the Strait of Malacca to the southern Indian Ocean.
Malaysian Defense Minister Hishammuddin Hussein made it clear Thursday that although international search efforts are continuing both on land and in sea in the northern and southern hemispheres, the effort is mostly concentrated south of the equator over the vast Indian Ocean.
Malaysian authorities have not ruled out any possible explanation for what happened to the jet, but have said the evidence so far suggests it was deliberately turned back across Malaysia to the Strait of Malacca, with its communications systems disabled. They are unsure what happened next.
Police are considering the possibility of hijacking, sabotage, terrorism or issues related to the mental health of the pilots or anyone else on board.